U.S. patent application number 10/556875 was filed with the patent office on 2006-09-28 for medical manipulator.
This patent application is currently assigned to Waseda University. Invention is credited to Masakatsu Fujie, Haruna Okayasu.
Application Number | 20060217686 10/556875 |
Document ID | / |
Family ID | 33475224 |
Filed Date | 2006-09-28 |
United States Patent
Application |
20060217686 |
Kind Code |
A1 |
Fujie; Masakatsu ; et
al. |
September 28, 2006 |
Medical manipulator
Abstract
A medical manipulator (10), comprising a plurality of
manipulator formed bodies (14) to (18) longitudinally connected to
each other so as be displaced relative to each other. The
manipulator formed bodies (14) to (18) further comprise bases (20)
and balloon bodies (21) installed on the bases (20) and providing
pressing forces to structures in a living body. The balloon bodies
(21) further comprise spaces (48) capable of storing normal saline
solution supplied from a device body (12), and installed so that
the pressing forces can be controlled by controlling internal
pressures in the spaces (48). The manipulator (10) is so formed as
to be autonomously moved forward in the living body by the control
of the pressing force while the manipulator formed bodies (14) to
(18) are displaced relative to each other by a reaction from the
structures in the living body.
Inventors: |
Fujie; Masakatsu; (Tokyo,
JP) ; Okayasu; Haruna; (Tokyo, JP) |
Correspondence
Address: |
WESTERMAN, HATTORI, DANIELS & ADRIAN, LLP
1250 CONNECTICUT AVENUE, NW
SUITE 700
WASHINGTON
DC
20036
US
|
Assignee: |
Waseda University
Tokyo
JP
|
Family ID: |
33475224 |
Appl. No.: |
10/556875 |
Filed: |
May 20, 2004 |
PCT Filed: |
May 20, 2004 |
PCT NO: |
PCT/JP04/06824 |
371 Date: |
November 15, 2005 |
Current U.S.
Class: |
606/1 |
Current CPC
Class: |
A61B 34/72 20160201;
A61B 2017/00557 20130101; A61B 17/0218 20130101; A61B 34/70
20160201; A61B 2017/320048 20130101 |
Class at
Publication: |
606/001 |
International
Class: |
A61B 17/00 20060101
A61B017/00 |
Foreign Application Data
Date |
Code |
Application Number |
May 22, 2003 |
JP |
2003-145056 |
Claims
1. A medical manipulator comprising a number of manipulator formed
bodies connected together in a longitudinal direction so as to be
relatively displaceable, the manipulator advancing in a living
body, wherein at least some of the manipulator formed bodies
comprise a base and a pressure section provided on the base to
exert a pressing force on tissues in the living body, the pressure
section comprises a space in which a predetermined fluid can be
accommodated, the pressing force can be adjusted by regulating an
internal pressure of the space, and adjustment of the pressing
force allows the manipulator formed bodies to advance autonomously
in the living body while being relatively displaced under a
reaction force from the tissues.
2. The medical manipulator according to claim 1, wherein the
pressure section comprises a balloon body that expands and deflates
in response to an increase and decrease in the amount of fluid
accommodated.
3. The medical manipulator according to claim 1 or 2, wherein the
pressure section is provided in each of the manipulator formed
bodies and the pressing force of each pressure section is
independently adjustable.
4. The medical manipulator according to claim 1 or 2, wherein the
pressure section is provided on both a upper and lower surfaces of
the base so as to press the tissues upward and downward with
respect to the base.
5. The medical manipulator according to claim 1 or 2, wherein a
channel is formed in the base so that the channel is in
communication with a space in the pressure section.
6. The medical manipulator according to claim 5, wherein connecting
means is provided between the bases to connect the bases so that
the bases can be relatively displaced, and a connecting passage is
formed in the connecting means to allow said channels formed in the
bases to be in communication with each other.
7. The medical manipulator according to claim 6, wherein the
connection passage is configured to keep the channels in
communication with each other even when the bases are relatively
displaced.
8. The medical manipulator according to claim 6, wherein the fluid
is normal saline solution, and the connecting passage allows
leakage of part of the normal saline solution passing through the
connecting passage so as to supply the normal saline solution to
the interior of the living body.
9. The medical manipulator according to claim 1 or 2, wherein
restricting means are provided between the manipulator formed
bodies so as to restrict the relative displacement of the
manipulator formed bodies.
Description
TECHNICAL FIELD
[0001] This invention relates to a medical manipulator, and more
specifically, to a medical manipulator that can autonomously
advance in a living body under a reaction force from tissues in the
living body and without the need for a propulsive force exerted by
a robot or the like.
BACKGROUND ART
[0002] A medical manipulator system is now prevailing which is used
to achieve minimally invasive surgery that do not involve a large
incision (see Patent Document 1). This medical manipulator system
comprises a manipulator provided with a surgical instrument such as
an endoscope or a treatment instrument at its front end and a robot
arm that grips the manipulator to move it in a predetermined
direction. With this system, an operator remotely operates the
robot arm to insert the manipulator into the body. The operator
then uses the instrument provided at the front end to for example,
treat the affected part. The instrument provided to be able to bend
by using a servo motor as a driving source to pull a plurality of
wires connected to the front end. Further, with this system, when
the manipulator runs out of control, the operator activates a
switch placed at his or her feet to shut down the system. The
operator can thus forcibly stop the operation of the
manipulator.
[Patent Document 1] Japanese Patent Publication No. 9-66056
[0003] However, since the medical manipulator system uses the robot
arm to move the manipulator, if the robot runs out of control, it
is inconveniently impossible to ensure that inadvertent movement of
the manipulator can be prevented. That is, to stop the manipulator
emergently when it runs out of control, the operator must activate
the switch. To perform this operation, the operator must recognize
that the manipulator is running out of control. During an
operation, the manipulator is likely to be present in the body.
Accordingly, it is difficult for the operator to see the
manipulator running out of control. This delays the finding of the
running out of control to prevent the manipulator from being
stopped immediately after the occurrence of the running out of
control. Further, if the operator quickly recognizes the occurrence
of the running out of control and immediately activates the switch,
the driving actuator for the robot arm is stopped. However, owing
to its inertia or the like, the manipulator is stopped slightly
later than the driving actuator. This is a serious problem for the
manipulator, which is inserted into the body, which provides the
manipulator with a narrow operational range. The delay in stop may
cause body tissues to be damaged.
[0004] Further, the above system uses a complicated mechanism
employing a metal wire, a servo motor, or the like, to provide to
be able to bend the manipulator. This precludes the safety of the
living body from being ensured when the mechanism is broken.
Further, it is necessary to complicate the whole system and to
increase the size of the system. That is, if the manipulator
inserted into the body was broken, electrical leak might occur
through the wire. Furthermore, since the driving source is the
servo motor, if a magnetic resonance imaging system (MRI) is used
with the manipulator, the servo motor must be separated
sufficiently from the MRI. This is to prevent the MRI from
affecting by the driving of the servo motor. That is, a main body
including the servo motor must be separated sufficiently from the
manipulator, located in proximity to the MRI. This requires a large
space in which the whole system is installed. Moreover, the above
system requires a wire winding mechanism. Accordingly, if the
manipulator has a multijoint structure, the winding mechanism must
further be complicated in order to wind each wire independently.
This increases the number of components required in the whole
system. Therefore, the system structure must be complicated.
DISCLOSURE OF THE INVENTION
[0005] The present invention is originated by taking notice of the
above inconveniences. It is an object of the present invention to
provide a medical manipulator that can be autonomously advanced in
a living body without the need to exert a propulsive force caused
by a robot or the like, and that manipulator is thus prevented from
running out of control.
[0006] It is another object of the present invention to provide a
medical manipulator which can keep a living body safe even when the
manipulator is broken, and which enables to be simplified and the
configuration of the whole system to facilitate a reduction in the
size of the system.
[0007] To attain these objects, the present invention provides a
medical manipulator comprising a number of manipulator formed
bodies connected together in a longitudinal direction so as to be
relatively displaceable, the manipulator advancing in a loving
body,
[0008] wherein at least some of the manipulator formed bodies
comprise a base and a pressure section provided on the base to
exert a pressing force on tissues in the living body,
[0009] the pressure section comprises a space in which a
predetermined fluid can be accommodated, the pressing force can be
adjusted by regulating an internal pressure of the space, and
adjustment of the pressing force allows the manipulator formed
bodies to advance autonomously in the living body while being
relatively displaced under a reaction force from the tissues.
[0010] With this configuration, when the manipulator advances
through a gap in the living body, the manipulator formed bodies are
relatively displaced under the reaction force from the tissues
present around the gap. Consequently, the interaction with the
tissues allows the manipulator to advance autonomously like a
looper while following the shape of the gap. This eliminates the
need for a robot that forces the manipulator to move in spite of
the presence of the tissues. It is thus possible to preclude
inadvertent movement of the manipulator resulting from the running
out of control of the robot. Further, since the manipulator formed
bodies are relatively displaced under the reaction force from the
tissues, the pressure section is prevented from exerting an
unnatural pressing force on the tissues. Therefore, the manipulator
can be used even for the brain, which is composed of soft tissues.
Moreover, while the manipulator is advancing, the manipulator
formed bodies are in a free state (passively controlled state) and
can be relatively displaced. This allows the manipulator to be
easily pulled out of the living body even if the system fails.
Further, it is unnecessary to provide any wires, motors, sensors,
or other mechanisms that relatively displace the manipulator formed
bodies. This makes it possible to avoid electrical leak through
wires when the manipulator is broken, thus improving safety.
Further, the entire configuration of the system including the
manipulator can be simplified to facilitate a reduction in the size
of the system. Moreover, the supply of a fluid allows the
manipulator formed bodies to be relatively displaced. Consequently,
if a magnetic resonance imaging system (MRI) is used with the
manipulator, the manipulator can suppress the adverse effect on
MRI. Further, owing to the correlation between the pressing force
on the tissues and the internal pressure of the space, the pressing
force on the tissues can be detected by measuring the internal
pressure of the space. Therefore, the manipulator can be allowed to
function as a pressure sensor.
[0011] According to the present invention, the pressure section is
preferably composed of a balloon body that expands and deflates in
response to an increase and decrease in the amount of fluid
accommodated.
[0012] This makes it possible to enlarge the gap in the living body
when the manipulator advances through the living body. The
manipulator can be advanced while pushing through the gap. Further,
the pressure section can be made flexible enough to prevent an
excessive pressing force from acting on the tissues constituting
the periphery of the gap.
[0013] Furthermore, preferably, the pressure section is provided in
each of the manipulator formed bodies and the pressure force of
each pressure section is independently adjustable.
[0014] This enables the position of the manipulator to be
complicatedly displaced. Consequently, the manipulator can be
easily advanced even if the gap in the living body through which
the manipulator is inserted has a complicated curved shape or the
like.
[0015] Moreover, preferably, the pressure section is provided on
both a upper and lower surfaces of base so as to press the tissues
upward and downward with respect to the base.
[0016] This arrangement enables the manipulator to advance
autonomously while exerting reduced pressing forces with the upward
and downward pressing forces balanced.
[0017] Further, preferably, a channel is formed in the base so that
the channel is in communication with a space in the pressure
section.
[0018] This arrangement eliminates the need for lines such as
external tubes which are used to supply a fluid to the space in the
pressure section. This simplifies the configuration of the
manipulator.
[0019] In this case, connecting means may be provided between the
bases to connect the bases so that the base scan be relatively
displaced, and a connecting passage may be formed in the connecting
means to allow said channels formed in the bases to be in
communication with each other.
[0020] This also simplifies the configuration of the manipulator to
enable the manipulator to advance smoothly.
[0021] In this case, the connection passage is configured to keep
the channels in communication with each other even when the bases
are relatively displaced.
[0022] With this arrangement, even if the area of engaging parts of
the connecting means decreases when the manipulator formed bodies
are relatively displaced, channels through which a fluid is
supplied to the space, can be provided. This makes it possible to
maintain the continuous advancement of the manipulator.
[0023] In this case, preferably, the fluid is normal saline
solution, and the connecting passage allows leakage of part of the
normal saline solution passing through the connecting passage so as
to supply the normal saline solution to the interior of the living
body.
[0024] With this arrangement, the normal saline solution can be
supplied to the living body during an operation or the like without
the need to insert for example, separate tubes for droplet into the
living body when the manipulator advances through the living body.
This minimizes the number of manipulators inserted into the gap in
the living body. Therefore, the present invention is useful even if
the gap is narrow.
[0025] Further, restricting means are provided between the
manipulator formed bodies so as to restrict the relative
displacement of the manipulator formed bodies. Thus, in the simple
configuration of the manipulator, it can be locked in any
positions.
[0026] In the description, the term "front" means a leading end of
the manipulator in its advancing direction and the term "rear"
means the opposite side unless otherwise specified. The term "width
direction" means a direction orthogonal to the advancing direction
of the manipulator as seen from above. If not otherwise specified,
the terms "upper" and "lower" mean one and the other ends of two
directions mutually orthogonal to the advancing direction of the
manipulator which direction does not correspond to the width
direction.
BEST MODE FOR CARRYING OUT THE INVENTION
[0027] Embodiments of the present invention will be described below
with reference to the drawings.
[0028] FIG. 1 shows a schematic plan view of a medical manipulator
in accordance with the present embodiment. FIG. 2 is a schematic
side view of the manipulator. In these figures, a manipulator 10 is
a leading manipulator that enlarges a gap in a living body. The
manipulator 10 allows an instrument manipulator (not shown) to be
easily inserted into the living body; the instrument manipulator is
provided with a surgical instrument, e.g., a scalpel at its front
end. The manipulator 10 has its rear end held by an apparatus main
body 12. The manipulator 10 consists of five manipulator formed
bodies 14 to 18 connected together in a longitudinal direction so
as to be relatively displaceable. In the description below, the
manipulator formed bodies 14 to 18 are called a first formed body
14, a second formed body 15, a third formed body 16, a fourth
formed body 17, and a fifth formed body 18.
[0029] The first formed body 14 comprises a base 20, and balloon
bodies 21 (see FIG. 2) provided over and under the base 20 and
serving as pressure sections that exert pressure forces to tissues
in the living body when the manipulator is inserted into the living
body.
[0030] As shown in FIGS. 3 to 5, the base 20 comprises a main body
23 shaped like an elongate piece having a curved front edge, and a
rear projecting piece 24 that projects rearward from a rear end of
the main body 23.
[0031] As shown in FIG. 6, the main body 23 consists of an upper
area 23A constituting nearly the upper half and a lower area 23B
constituting nearly the lower half. An upper channel 26 and a lower
channel 27 are formed inside the upper area 23A and lower area 23B,
respectively, so that normal saline solution supplied by the
apparatus main body 12 (see FIG. 1 and the like) passes through the
upper channel 26 and lower channel 27. As shown in FIGS. 5 and 6,
the upper channel 26 consists of one upper first supply channel 29
extended in the longitudinal direction. The upper first supply
channel 29 is in communication with an upper supply hole 32 that is
open on an upper surface of the main body 23. On the other hand,
the lower channel 27 consists of one lower first supply channel 30
extended in the longitudinal direction along a position where it
does not interfere with the upper first supply channel 29. The
lower first supply channel 30 is in communication with a lower
supply hole 33 that is open on a lower surface of the main body
23.
[0032] As shown in FIGS. 3 to 6, the rear projecting piece 24
consists of a pair of rear side pieces 35, 35 located at the both
ends in the width direction and two rear intermediate pieces 37, 37
located between the rear side pieces 35, 35. The rear side pieces
35 and rear intermediate pieces 37 are not particularly limited but
are formed so as to have an external shape linearly extending
rearward from their base end and having a semicircular rear
end.
[0033] Each rear side piece 35 is provided with an inwardly open
concave portion 39 located virtually in the center of the rear side
piece. The concave-portion 39 has a virtually circular external
shape in a front view. The concave portion 39 is shaped like a
tapered hole having an internal dimension decreasing gradually from
its open side toward the interior as shown in FIG. 5.
[0034] Each of the rear intermediate piece 37 comprises an inner
side surface 37A and an outer side surface 37B located at the both
ends in the width direction, a shaft insertion hole 42 penetrating
the rear intermediate piece 37 virtually in its center in the width
direction, and a connecting passage 44 that is in communication
with the upper channel 26 and lower channel 27 at positions where
the connecting passage 44 does not interfere with the shaft
insertion hole 42. The term "inner side surface 37A" means a side
surface facing the another rear intermediate piece 37. The term
"outer side surface 37B" means a side surface lying opposite the
inner side surface 37A.
[0035] The connecting passage 44 consists of an upper connecting
passage 44A formed in an upper area of the rear intermediate piece
37 located in the upper side of FIG. 5, and a lower connecting
passage 44B formed in a lower area of the rear intermediate piece
37 located in the lower side of FIG. 5. The upper connecting
passage 44A is in communication with the upper first supply channel
29, formed in the upper area 23A of the main body 23. The upper
connecting passage 44A extends rearward from the upper first supply
passage 29 and bends to the width direction in the middle of the
passage. The upper connecting passage 44A is thus open on the inner
side surface 37A. On the other hand, the lower connecting passage
44B is in communication with the lower first supply channel 30,
formed in the lower area 23B of the main body 23. The lower
connecting passage 44B extends rearward from the lower first supply
passage 30 and bends to the width direction in the middle of the
passage. The lower connecting passage 44B is thus open on the inner
side surface 37A. As shown in FIGS. 3 and 4, open portions 46 of
the upper connecting passage 44A and lower connecting passage 44B
constitute slots having an external shape similar to fans and are
formed to have virtually the same shape and size. Further, as shown
in FIG. 6, the open portions 46 are formed to be symmetrical in the
lateral and to be symmetrical in vertical directions between the
FIGS. 6(A) and 6(B).
[0036] As shown in FIG. 2, the balloon bodies 21 are fixed along
each periphery of upper and lower surfaces of the base 20. The
interiors of the balloon bodies 21 constitute spaces 48 in which
the normal saline solution flowing out through the upper supply
hole 32 and the lower supply hole 33 (see FIG. 3) is accommodated.
The balloon bodies 21 are formed of an elastic material such as
latex which has a high biocompatibility. The balloon bodies 21
expand and deflate in response to an increase and decrease in the
amount of the normal saline solution accommodated. In its initial
state in which no normal saline solution is accommodated in the
space 48, each of the balloon bodies 21 is placed like a sheet
along a surface of the base 20 as shown by a chain double-dashed
line in the figure. On the other hand, as the normal saline
solution is supplied to the space 48, the balloon body 21 inflates
away from the base 20 as shown by a solid line in FIG. 2.
[0037] Now, the second to fifth formed bodies 15 to 18 will be
described. Almost all the formed bodies 15 to 18 have components
that are substantially the same as or equivalent to those of the
first formed body 14. The same or equivalent components are denoted
by the same reference signs and their description will be omitted
or be brief.
[0038] As shown in FIGS. 3, 4, and 7, the second formed body 15
further comprises a front projecting piece 50 projecting frontward
from a front end of the main body 23. The front projecting piece 50
is shaped so that it can engage with the rear projecting piece 24
of the first formed body 14. That is, the projecting piece 50
consists of a pair of front side pieces 52, 52 received in the gap
between the rear side piece 35 and the rear intermediate piece 37,
and a front intermediate piece 53 received in the gap between the
opposite rear intermediate pieces 37, 37. The front side pieces 52
and the front intermediate pieces 53 are not particularly limited
but are formed so as to have an external shape linearly extending
frontward from their base end and having a semicircular front
end.
[0039] A member accommodating hole 55 is formed in the front side
piece 52 so as to penetrate the front side piece 52 in the width
direction virtually in its center. The member accommodating hole 55
is shaped like a stepped hole consisting of a larger diameter
portion 55A located outside in the width direction and a smaller
diameter portion 55B connected to the larger diameter portion 55A
and extending inward in the width direction. As shown in FIG. 7,
piece member 57 that virtually shaped a frustum of a cone is
accommodated in the larger diameter portion 55A. The piece member
57 is formed to have a size that can be accommodated in the larger
diameter portion 55A while the piece member 57 can move outward in
the width direction. Further, the shape of top of the piece member
57 is virtually the same as the internal shape of the concave
portion 39, formed in the rear side piece 35. That is, when the
piece member 57 is moved outward in the width direction as
described below with the first and second formed bodies 14 and 15
connected together, the top of the piece member 57 is fitted into
the concave portion 39 so as to inhibit their relative rotations.
The smaller diameter portion 55B is set to have virtually the same
inner diameter as that of the shaft insertion hole 42 formed in the
rear projecting piece 24 of the first formed body 14.
[0040] The front intermediate piece 53 comprises a shaft insertion
hole 59 penetrating the front intermediate piece 53 in the width
direction virtually in its center, and a connecting passage 60
located at a position where the connecting passage 60 does not
interfere with the shaft insertion hole 59.
[0041] The shaft insertion hole 59 is set to have virtually the
same inner diameter as those of the shaft insertion hole 42 and
smaller diameter portion 55B. When the rear projecting piece 24
engages with the front projecting piece 50, the shaft insertion
hole 59 communicates with the shaft insertion hole 42 and smaller
diameter portion 55B. While the shaft insertion hole 59 is in
communication with the shaft insertion hole 42 and smaller diameter
portion 55B, a pipe-like shaft member 62 is inserted through the
shaft insertion holes 42 and 59 and smaller diameter portion 55B
(see chain double-dashed lines in FIG. 7). This allows the first
and second formed bodies 14 and 15 to be connected together so that
they are relatively rotatable in the vertical direction. Therefore,
the rear projecting piece 24, the front projecting piece 50, and
the shaft member 62 constitute connecting means for connecting the
bases 20, 20 together so as to be relatively displaceable. The
shaft member 62 has an outer diameter that is virtually the same as
the inner diameter of the shaft insertion holes 42 and 59 and
smaller diameter portion 55B. Further, the shaft member 62 is long
enough to allow its opposite ends to project into the large
diameter portion 55A when inserted through the holes 42, 59, and
55B (see chain double-dashed lines in FIG. 7). When the piece
member 57 and the shaft member 62 are assembled together, virtually
the entire area of the piece member 57 is accommodated in the
larger diameter portion 55A in the state of contacting between the
bottom of the piece member 57 and a projecting portion of the shaft
member 62. At this time, a gap 58 (see FIG. 7) is formed around the
shaft member 62.
[0042] As shown in FIG. 7, the connecting passage 60 consists of an
upper connecting passage 60A formed in an upper area of the
intermediate piece 53, and a lower connecting passage 60B formed in
a lower area of the intermediate piece 53 so as not to interfere
with the upper connecting passage 60A. The connecting passages 60A
and 60B are open to the exterior in opposite side surfaces of the
intermediate piece 53. The connecting passage 60A and 60B are
shaped like channels extending in the width direction from an open
portion 64, bending in the middle of the passages, and then
extending rearward. The open portion 64 of the upper connecting
passage 60A is open to the top of FIG. 7, whereas the open portion
64 of the lower connecting passage 60B is open to the bottom of
FIG. 7. The open portions 64, 64 have virtually the same shape and
size of the open portions 46, 46 in the rear intermediate pieces
37, 37. When the first and second formed bodies 14 and 15 are
connected together so as to stand virtually in a line (hereinafter
this state will simply be referred to as a "linearly connected
position"), the open portions 46 lie opposite the open portions 64
so that each entire area of the open portions are virtually
overlapped on each other (see FIG. 8(A)). In this state, the upper
connecting passages 44A and 60A in the first and second formed
bodies 14 and 15 communicate with each other, and the lower
connecting passages 44B and 60B communicate with each other. Then,
the first and second formed bodies 14 and 15 are relatively rotated
to displace from the linearly connected position to a state in
which the first and second formed bodies 14 and 15 are connected
together while being bent (hereinafter this state will simply be
referred to as a "bending connected position"). Then, as shown in
FIGS. 8(B) and 8(C), the area in which the open portions 46, 64
overlap (overlapping area 66) decreases with increasing
displacement amount (relative rotation amount). On the other hand,
the area in which the open portions 46, 64 do not overlap
(non-overlapping area 67) increases gradually. In FIG. 8, to avoid
confusing in the figure, the contour line of the open portion 64 is
shown slightly smaller than that of the open portion 46.
[0043] As shown in FIGS. 7 and 9, the upper channel 26 in the
second formed body 15 consists of the upper first supply channel
29, that is in communication with the upper connection passage 60A,
an upper second supply channel 69 that is in communication with the
upper supply hole 32 which is open on the upper surface of the base
20 of the second formed body 15, and an upper braking channel 70
that is in communication with the member accommodating hole 55 in
the lower side of FIG. 7. The channels 29, 69, and 70 extend
virtually along the longitudinal direction in positions where they
do not interfere with one another.
[0044] The lower channel 27 and upper channel 26 in the second
formed body 15 are virtually symmetrical in the vertical direction
and the width direction. The lower channel 27 consists of the lower
first supply channel 30 that is in communication with the lower
connecting passage 60B, a lower second supply channel 72 that is in
communication with the lower supply hole 33 which is open on the
lower surface of base 20 of the second formed body 15, and a lower
braking channel 73 that is in communication with the member
accommodating hole 55 in the upper side of FIG. 7.
[0045] The braking channels 70 and 73 are in communication with the
large diameter portion 55A and particularly with a part of the
large diameter portion 55A which is closer to its bottom, that is,
to the smaller diameter portion 55B. Specifically, as shown only in
the member accommodating hole 55 in the upper side of FIG. 7, the
braking channels 70 and 73 are allowed to communicate with the gap
58 when the piece member 57 and the shaft member 62 are assembled
together.
[0046] In the second formed body 15, the rear intermediate piece 37
is placed at three places between the rear side pieces 35 and 35.
In each rear intermediate piece 37, the upper connecting passage
44A and the lower connecting passage 44B are formed along positions
where they do not interfere with each other, similarly to the
connecting channels 60A and 60B in the front intermediate piece 53.
The upper connecting passage 44A opens downward in FIG. 7 and is in
communication with the upper channel 26. That is, the upper
connecting channel 44A is in communication with the first supply
channel 29, the upper second supply channel 69, and the upper
braking channel 70 in order from the top to bottom of the figure.
The lower connecting passage 44B opens upward in FIG. 7 and is in
communication with the upper channel 27. That is, the lower
connecting channel 44B is in communication with the lower braking
channel 73, the lower second supply channel 72, and the lower first
supply channel 30 in order from the top to bottom of the
figure.
[0047] As shown in the conceptual drawing of FIG. 10 showing the
configuration of the channels, the third formed body 16 has one
more front intermediate piece 53 and one more rear intermediate
piece 37 than the second formed body 15. In contrast to the second
formed body 15, the third formed body 16 has an upper third supply
channel 75 that is in communication with the upper supply hole 32
which is open on the upper surface of the base 20, and a lower
third supply channel 76 that is in communication with the lower
supply hole 33 which is open on the lower surface of the base 20.
In FIG. 10, channels shown by solid lines are formed in the upper
area of the base 20, whereas channels shown by dashed lines are
formed in the lower area of the base 20.
[0048] A connecting structure for the second and third formed
bodies 15 and 16 is the same as that for the first and second
formed bodies 14 and 15, already described. Note that, with the
second and third formed bodies 15 and 16 connected together (see
FIG. 10(B)), the upper braking channel 70 and lower braking channel
73 in the second formed body 15 are in communication with the
member accommodating holes 55, 55 in the third formed body 16 as
previously described.
[0049] Although not shown in the figure, the fourth formed body 17
has one more front intermediate piece 53 and one more rear
intermediate piece 37 than the forward adjacent formed body 16, and
the fifth formed body 18 has one more front intermediate piece 53
and one more rear intermediate piece 37 than the forward adjacent
formed body 17. Further, in contrast to the third formed body 16,
the fourth formed body 17 has additional supply channels that are
in communication with the supply holes 32 and 33, and in contrast
to the fourth formed body 17, the fifth formed body 18 has
additional supply channels that are in communication with the
supply holes 32 and 33. The connected state among the adjacent
formed bodies 16, 17, and 18 is virtually the same as that between
the second and third formed bodies 15 and 16.
[0050] As described above, in the manipulator 10, the supply
channels 29, 30, 69, 72, 75, 76, . . . , that are in communication
with the space 48 (see FIG. 2) in each balloon body 21, are formed
inside each base 20 so that the channels are independently
connected to the rear apparatus main body 12. The channels also
allow the formed bodies 14 to 18 to be relatively displaced while
maintaining the above state. Further, the upper braking channels 70
in the second to fifth formed bodies 15 to 18 are connected
together and to the apparatus main body 12 while allowing the
formed bodies 15 to 18 to be relatively displaced. The lower
braking channels 73 in the second to fifth formed bodies 15 to 18
are also connected together and to the apparatus main body 12 while
allowing the formed bodies 15 to 18 to be relatively displaced.
[0051] The apparatus main body 12 includes a heretofore-known pump
apparatus that can independently supply normal saline solution to
each of the upper channels 26 and lower channels 27. The apparatus
main body 12 can control the flow rate and pressure of the normal
saline solution ejected.
[0052] Operating the apparatus main body 12 enables the manipulator
10 configured as described above to independently supply normal
saline solution to the space 48 in any of the balloon bodies 21;
the flow rate and pressure of the normal saline solution is under
control. Further, when the apparatus main body 12 supplies normal
saline solution to the braking channels 70 and 73, the normal
saline solution reaches the gap 58 (see FIG. 7) in the member
accommodating hole 55. The water pressure moves the piece member 57
outward. Then, the piece member 57 is thus fitted into the
corresponding concave portion 39 so that the piece member 57 cannot
be relatively rotated to concave portion 39. This restricts the
relative displacement of the formed bodies 14 to 18 to lock the
manipulator 10 in a predetermined position. Therefore, the concave
portion 39, the piece member 57, the member accommodating hole 55,
and the braking channels 70 and 73 constitute restricting means for
restricting the relative displacement of the base 20 using the
pressure of the fluid.
[0053] Moreover, the adjacent manipulator formed bodies 14 to 18
are displaced from the linearly connected position as a reference
position, to the bending connected position. At this time, the open
portions 46 and 64 that constitute the joints between the
connecting passages 44 and 60 located in the connecting portion,
are shifted in the relatively rotating direction, as previously
described. Therefore, this forms a non-overlapping area 67 (see
FIG. 8) where the open portions 46 and 64 do not overlap. Then, the
normal saline solution leaks from the non-overlapping area 67 to
the exterior of the manipulator 10. The size of the non-overlapping
area 67 is designed so that in spite of leakage, the normal saline
solution can reach the supply hole 32 and 33 and the member
accommodating hole 55. The open portions 46 and 64 form an
overlapping area 66 (see FIG. 8) even when the adjacent manipulator
formed bodies 14 to 18 are displaced in a bending connected
position. Consequently, even during the relative displacement, the
connecting passages 44 and 60 remain in communication.
[0054] When the manipulator 10 is inserted into for example, the
brain, the normal saline solution in the apparatus main body 12
(see FIG. 1) starts to be supplied with the front end of the
manipulator 10 set near an inlet of a gap S in the brain B as shown
in FIG. 11. The balloon bodies 21 are then expanded starting from
their front ends. In this case, the balloon bodies 21 with a
predetermined elasticity softly press a brain tissue B1 around the
gap S. The internal pressures of the opposite upper and lower
balloon bodies 21, 21 are independently adjusted to regulate a
pressing force exerted on the brain tissue B1 by each balloon body
21. When the pressing force on the brain tissue B1 is thus
regulated in accordance with the shape of the gap S, the
manipulator formed bodies 14 to 18 of the manipulator 10 are
displaced between the linearly connected position and the bending
connected position under the reaction force from a brain tissue B1
while following the shape of the gap S. The manipulator 10
autonomously advances toward the affected part while pushing
through the gap S like a looper. On this occasion, as previously
described part of the normal saline solution leaks from the joints
between the manipulator formed bodies 14 to 18 into the gap S. The
leaking normal saline solution can be utilized as droplet for the
brain tissue B during a surgery. Once the front end of the
manipulator 10 reaches the affected part, the apparatus main body
12 supplies the normal saline solution to the braking channels 70
and 73 (see FIG. 7 or other figures). Each piece member 57 is moved
outward to lock the manipulator 10 to disable the relative
displacement of the manipulator formed bodies 14 to 18. Almost
simultaneously with this, as shown in FIG. 12, another manipulator
10 is inserted into the gap S in a manner similar to that
previously described. The balloon bodies 21 are expanded to enlarge
the gap S to provide a passage through which the instrument
manipulator (not shown) can be inserted. By measuring the internal
pressure of each balloon body 21 that is in contact with the brain
tissue B1, it is possible to detect, for each relevant site, the
pressing force exerted on the brain tissue B1 by the balloon body
21. That is, the manipulator 10 also functions as a pressure sensor
that can detect the pressing force on the brain tissue B1.
[0055] Accordingly, this embodiment eliminates the need for a robot
or the like which advances the manipulator 10 and thus prevents the
running out of control of the manipulator 10 associated with the
use of a robot. The manipulator 10 can thus be safely moved in the
living body. The embodiment also eliminates the need for a wire or
motor that serve as a mechanism for displacing the position of the
manipulator 10. Consequently, even if the manipulator 10 is broken,
electrical leak does not occur in the living body, thus improving
safety. The embodiment is also effective in simplifying and
miniaturizing the whole system including the manipulator 10.
Moreover, the embodiment can be used as means for supplying droplet
during an operation or as a pressure sensor that can detect the
pressing force on the interior of the living body. The embodiment
can thus be suitably used for a narrow gap S such as the interior
of the brain B.
[0056] A variation of the embodiment will be described with
reference to FIGS. 13 and 14.
[0057] The present variation is characterized by the simplified
structure of the manipulator 10. The same reference signs will be
used for structural elements in the variation which are
substantially the same as or equivalent to those in the above
embodiment. The description of these elements will be omitted or
simplified. In FIG. 13, channels shown by solid lines are formed in
the upper area of the base 20. Channels shown by alternate long and
short dash lines are formed in the lower area of the base 20.
[0058] In the present variation, the rear projecting pieces 24 of
the first to fifth formed bodies 14 to 18 have substantially the
same shape. The front projecting pieces 50 of the first to fifth
formed bodies 15 to 18 have substantially the same shape. No
channels for the normal saline solution are provided in the
projecting pieces 24 or 50. Flexible pipes P are used to connect
together channels with the same reference sign formed in the formed
bodies 14 to 18. The channels are connected to the apparatus main
body 12 (see FIG. 1). Each of the rear projecting pieces 24 is
composed of the pair of rear intermediate pieces 37, 37, in which
the shaft insertion hole 42 is formed. On the other hand, the front
projecting piece 50 is composed of the front intermediate piece 53,
positioned between the rear intermediate pieces 37 and 37. The
shaft insertion hole 59 is formed in the front intermediate piece
53 so that the shaft insertion hole 59 is in communication with the
shaft insertion hole 42 and so that the shaft member 62 can be
inserted through the shaft insertion hole 59. In the present
variation, the rear projecting piece 24 and the front projecting
piece 50 are connected together so as to be relatively rotatable.
The pipes P are arranged outside the rear intermediate pieces 37,
37.
[0059] An accommodating hole 82 is formed between the rear
intermediate pieces 37 and 37 of each of the formed bodies 14 to 18
so that a block-shaped stopper 81 is accommodated in the
accommodating hole 82. The stopper 81 is movable through the
accommodating hole 82 in the longitudinal direction (lateral
direction of FIG. 14). A rear end of the accommodating hole 82 is
open. A leading edge 82A of the stopper 81 slides out of and back
into the open portion. The leading edge 82A is wedged and can slide
out of the open portion and engage with a peripheral surface of the
intermediate piece 53. A fixed portion 83, 83 (see FIG. 14) for a
wire W extending toward the apparatus body 12 is provided on both
the upper and lower surfaces of the stopper 81. The fixed portions
83, 83 of the formed bodies 14 to 18 are connected together using
the wires W. The upper and lower wires W can be wound using a wire
winding device (not shown) in the apparatus main body 12. That is,
when the wire winding device is activated, the upper and lower
wires W are simultaneously pulled toward the apparatus main body
12. The stoppers 81 in the formed bodies 14 to 18 are
simultaneously moved rearward. Then, each of the leading edges 82A
of the stoppers 81 engages with the front intermediate piece 53 to
restrict the relative rotation of the rear projecting piece 24 and
front projecting piece 50. Accordingly, the stopper 81, the
accommodating hole 82, the fixed portions 83, and the wires W
constitute restricting means for restricting the relative rotation
of each base 20. On the other hand, when the wire winding device
stops its operation to allow the wires W to be relaxed, the
restriction on the relative rotation of each base 20 is cancelled.
A biasing means such as a spring may be provided between the
stopper 81 and the accommodating hole 82 so that when the wire
winding device stops its operation, the leading edge 82A of the
stopper 81 moves away from the front intermediate piece 53.
[0060] In the above embodiment, the present invention is applied to
the leading manipulator. However, the present invention is not
limited to this but is applicable to other manipulators such as
instrument manipulators.
[0061] Further, the number of manipulator formed bodies 14 to 18
constituting the manipulator 10 is not limited to the one in
accordance with the embodiment. The number of manipulator formed
bodies can be increased or reduced. The number of balloon bodies 21
can also be increased or reduced unless the autonomous advancement
of the manipulator 10 is hindered.
[0062] The fluid supplied to the interior of the balloon body 21 is
not limited to the normal saline solution. Another fluid such as a
liquid or gas is applicable, as long as that it exerts the above
effects and does not affect the living body. However, if any
balloon body 21 was broken, the use of the normal saline solution
alleviates the adverse effect on the living body because a larger
amount of normal saline solution is simply supplied to the interior
of the living body.
[0063] The configuration of each section of the present invention
is not limited to the illustrated one. Many variations may be made
to the configuration as long as it exerts substantially similar
effects.
[0064] As described above, the present invention enables the
manipulator to advance in the living body without the need for an
external propulsive force exerted by a robot or the like. Thus, the
manipulator can be autonomously moved in the living body while
being prevented from running out of control.
[0065] Further, the supply of the fluid activates the manipulator,
thus improving the safety of the living body when the manipulator
is broken. Moreover, the configuration of the whole system can be
simplified to further reduce the size of the system.
INDUSTRIAL APPLICABILITY
[0066] During automatic advancement, the manipulator is prevented
from running out of control. The manipulator is therefore suitable
as a safe medical instrument.
BRIEF DESCRIPTION OF THE DRAWINGS
[0067] [FIG. 1] is a schematic plan view of a manipulator in
accordance with the present embodiment;
[0068] [FIG. 2] is a schematic side view of the manipulator;
[0069] [FIG. 3] is an exploded perspective view of a first and a
second formed bodies;
[0070] [FIG. 4] is an exploded perspective view as viewed from a
direction opposite to that in FIG. 3;
[0071] [FIG. 5] is a schematic transverse sectional view of the
first formed body;
[0072] [FIG. 6] (A) is a vertical sectional view taken along line
A-A in FIG. 5, and (B) is a vertical sectional view taken along
line B-B in FIG. 5;
[0073] [FIG. 7] is a schematic transverse sectional view of the
first formed body;
[0074] [FIGS. 8](A) to (C) are conceptual drawings illustrating the
relationship between open portions during a displacing operation
for bending;
[0075] [FIG. 9] is a vertical sectional view taken along line C-C
in FIG. 7;
[0076] [FIG. 10] (A) is a schematic plan view showing a channel
configuration in the state of disassembly of the first, second, and
third formed bodies, and (B) is a schematic plan view showing a
channel configuration in the state of the connection of the first,
second, and third formed bodies;
[0077] [FIGS. 11](A) to (C) are conceptual drawings illustrating a
procedure of advancing the manipulator into the brain;
[0078] [FIGS. 12] (A) to (C) are continued drawings of FIG. 11
illustrating the procedure of advancing the manipulator into the
brain;
[0079] [FIG. 13] is a schematic plan view showing a channel
configuration in the state of the connection of the first, second,
and third formed bodies in accordance with a variation of the
embodiment; and
[0080] [FIG. 14] is a sectional view taken along line A-A in FIG.
13.
DESCRIPTION OF SIGNS
[0081] 10 Manipulator [0082] 14 First formed body (manipulator
formed body) [0083] 15 Second formed body (manipulator formed body)
[0084] 16 Third formed body (manipulator formed body) [0085] 17
Fourth formed body (manipulator formed body) [0086] 18 Fifth formed
body (manipulator formed body) [0087] 20 Base [0088] 21 Balloon
body [0089] 24 Rear projecting piece (connecting means) [0090] 26
Upper channel [0091] 27 Lower channel [0092] 39 Concave portion
(restricting means) [0093] 44 Connecting passage [0094] 48 Space
[0095] 50 Front projecting piece (connecting means) [0096] 55
Member accommodating hole (restricting means) [0097] 57 Piece
member (restricting means) [0098] 62 Shaft member (connecting
means) [0099] 70 Upper braking channel (restricting means) [0100]
73 Lower braking channel (restricting means) [0101] 81 Stopper
(restricting means) [0102] 82 Accommodating hole (restricting
means) [0103] 83 Fixed portion (restricting means) [0104] W Wire
(restricting means)
* * * * *